The subject of critical thinking has occupied central position in debates
             concerning education, cognitive development and personality formation. For
             this reason, the term critical thinking has repeatedly been defined taking
             into consideration new research and new findings. However no specific or
             unanimously accepted definition of critical thinking is available, making
             the comprehension and learning of critical thinking a rather difficult
             task. The increasing important of critical thinking however makes it
             impossible to ignore the term and or its impact on learning and
             intellectual development and for this reason; we shall discuss various
             differing definitions of critical thinking. We shall focus on the
             definitions from early 20th century to recent times in order to see the
             differences that have occurred and the similarities that remained in the
             definitions of this term over the decades. John Dewey was one of the early
             thinkers to develop and present a sound definition of critical thinking. To
             him critical thinking was reflective thinking' which he defined as:
             "Active, persistent, and careful consideration of any belief or
             supposed form of knowledge in the light of the grounds that support it
             and the further conclusions to which it tends" (Dewey, 1909, p.9)
             This definition is considered the mother of all definitions because we
             notice that most subsequent definitions borrowed heavily from the Dewey's
             ground rules of critical thinking. In this definition, critical thinking
             was compared with traditional normal thinking that we mostly engage in and
             the thinker makes it clear that compared to conventional thinking style,
             critical thinking was an active process. It was active because in this
             case, the subject himself is actively involved in evaluation of information
             Dewey's definition was widely accepted for a long time, in 1941, Edward
             Glaser came up with anther important de...